Categorization of Coal Based on Composition and Mineralogical Analysis for Evaluation of Quality Indicators; A Case Study of the Botor Tolay Area, Jimma, Southwestern Ethiopia
No Thumbnail Available
Date
2025-05
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Addis Ababa University
Abstract
The classification of the coal's composition from the Botor Tolay deposit and its implications for coal quality indicators are the main goals of this study. The project research employs analysis of coal samples collected from five points within the studied area, utilizing techniques such as proximate, calorific value, sulfur content, XRD, XRF, and FTIR analysis methods to determine key compositional elements. The results reveal distinct categories of coal based on their calorific value, sulfur presence, moisture content, ash content, volatile matter, fixed carbon, and fuel ratio. Accordingly, calorific value ranged from (7,406.54 to 9,783.46Btu/lb), sulfur content (0.17 to 0.21%), moisture content (1.12 to 1.46%), ash content (33.99 to 48.52%), volatile matter (19.13-21.94%), fixed carbon (30.84 to 42.88%) and fuel ratio (1.61 to 1.95%). Hence, all the studied coal samples fall within the sub-bituminous coal category based on calorific value categorization. One of the coals sample BT-1 has the highest percentage of fixed carbon (42.88%), which made it to have a high fuel ratio, enabling it to be more combustible. Major element analysis of the coal sample indicates it contains the maximum amount of SiO2 (67.668% by wt.), and Al2O3 (24.194% by wt.) followed by Fe2O3 (4.472% by wt.) and (TiO2 (1.296% by wt.). Functional group analysis indicated the presence of the peak of the -OH stretching vibration group and the peak in the spectra of coal found between 1100 and 400 cm−1, which are assigned to clay minerals such as quartz, kaolinite, and illite. The Crystal chemistry structure analysis of the coal sample revealed the presence of silicon dioxide (SiO2) and pyrite (FeS2), which may contribute to increased ash content.
Description
Keywords
coal categorization, quality, proximate analysis, calorific value